The present invention relates generally to improved support structures, and more particularly to improved stanchions capable of supporting one or more elevated tubular structures, for example a guideway, which may in turn carry a plurality of carriages for travel thereupon.
Elevated rail systems are well known in the art. However, most such systems have been developed for use in cities where the speed of the vehicles are relatively low. Rail systems between cities are typically placed upon the ground if possible, and to this end considerable grade development is involved to make the track bed as straight and level as possible. When high speed systems are developed, even more effort is made to insure level and straight right-of-ways. Elevated structures have been used between cities only where the terrain will not support a road bed as desired, typically to cross rivers and the like.
Ground level right-of-ways are becoming increasingly expensive and it is desirable to produce an elevated high speed passenger transport system between major cities. To this end it is necessary to provide an interurban elevated system.
Prior art elevated systems are known. Typical examples are U.S. Pat. Nos. 3,238,894, 3,534,689, 4,274,336, 4,632,038, 4,665,830, 5,027,713, and 5,809,897, German 196 38 578, Great Britain 2 305 645, and PCT printed application WO 96/27516. Finally, U.S. Pat. No. 4,181,995 discloses a bridging structure for road or rail traffic. However, none of these patents disclose an elevated roadway which can be used between cities where there is a design which is capable of passing along existing right-of-ways, for traversing over rolling or mountainous terrain, and for crossing rivers of moderate size.
It is also known to support elevated tubular structures, such as pipe lines. U.S. Pat. No. 4,128,219 discloses an elevated pipeline. But, as can be seen from this patent, little thought has been given to providing supports for a pipeline over rolling terrain where one of the objects is to keep the pipeline relatively straight. Furthermore, little thought has been given to developing a support structure which has equal vertical temperature expansion and has effectively equal load bearing resilience. There are two known methods for accommodating the expansion of a tube or pipeline. In one design, frequent (relatively closely spaced) xe2x80x9cUxe2x80x9d bends in the tube are employed. In a second design, closely spaced pressure sealing expansion joints are used. Both methods are expensive, requiring more structural support, while the xe2x80x9cUxe2x80x9d bends impede the internal flow and become excessively long with large diameter pipes or tubes. It is therefore very desirable to locate expansion mechanisms as far apart along the tubes as reasonable, the pressure compensated pipeline junction expansion joint is better suited for this purpose than the xe2x80x9cUxe2x80x9d bend (for pressurized large tubes). However, the tube or pipeline must be adequately supported while it is expanding and contracting. The pressure compensated pipeline junction expansion joint can easily function over an expansion range of 100 feet, so that the joints, (one at each end of a tube section), may be as much as 22 miles apart. This design is shown in applicants copending application Ser. No. 09/593,788, filed Jun. 14, 2000, for a PRESSURE COMPENSATED PIPELINE JUNCTION.
It is an object of the present invention to provide improved support structure capable of supporting a railway, roadway, or pipeline.
More particularly, it is an object of the present invention to provide improved support structure capable of supporting a guideway in the form of a tube or tubes which may in turn carry a train for travel thereupon, which elevated guideway is capable of passing over existing right-of-ways, rolling or mountainous terrain, and rivers of moderate size, the improved support structure providing a uniform vertical thermal expansion and uniform loading deflection (due to the weight of a passing train) thus assuring that the elevated tubes are smooth and straight.
It is a further object of the present invention to provide an improved support structure for a guideway which accommodate supporting the guideway on novel stanchions, and by unlimited expansion of the guideway by passing the guideway across the stanchion on rollers.
It is another object of the present invention to utilize the inherent stiffness of the tubes of the elevated guideway to further assure that they are smooth and straight.
Another object of the present invention is to provide a support structure including stanchions and ground footings, wherein at least as many as three tube spans may be carried between stanchion ground footings.
A further object of the present invention is to provide virtually unlimited guideway height with a minimal number of structural components.
Yet another object of the present invention is to provide a support structure which may be linked to other support structures in a continuous series without the use of expansion joints, each support structure including a guideway tube assembly which forms a continuous structure for supporting the roadway, railway or pipeline, and a xe2x80x9cTxe2x80x9d bar assembly for preventing rotation of the guideway tube assembly about a longitudinally extending axis.
A still further object of the present invention is to provide a support structure which has an aesthetically acceptable appearance.
The foregoing objects of this invention will be more fully understood after a consideration of the following detailed description taken in conjunction with the following drawings.